:Hi Sam: I am a retired EE university professor and am sorry you got "snake bit" by some rogue. I repair vintage electronics every day all day when I am not consulting. I am in south Georgia and if you will send me your Hickok I will troubleshoot it and phone you as to the problem and return it to you at absolutely no charge should you desire not to repair it. I have been in business since l954. :::::::I have a Hickok 6000A tube tester. It does not work--at all. The unit exhibits no life. I looked in the manual troubleshooting section. Most likely, the problem is either a bad line cord, a bad rectifier tube (or tubes),:::::or a transformer short. I am a novice. I can't even figure out how to get inside the tester without taking out about twenty screws. I am extremely :::::flustered, to say the least. ::::::::::Can you help me? Telling me who can "fix" the tester would be OK.:::::::::::::::::::If you have a manual for your tube tester check page 11 for a trouble shooting chart. If you don't have one go to ( bama.edebris.com) and download one.If you want to spend some bucks (alltubetesters.com)is a great site for info as well as parts and service.I bought a new panel meter for my Hickok 600A there.I fixed my own and it still cost me $350.It took me a week to learn it and get use to the calibration procedures but the result was worth it.Good Luck with it! Bob Masse::::Sorry about the mixed up reply(s)--I've never used this site before.::Thanks for your response.:::::::::: ::::::::